Posts Tagged ‘brain’

The human brain has about 85 billion neurons, most connected to thousands of others, making for trillions of connections – the most complex object known. I’ve written before about what wonders it performs.

Recently in a newspaper I came to a page full of text of no interest, and quickly turned the page. But I said to myself, “Did I see the word breasts?” With scientific curiosity, I went back and searched; sure enough, there it was, buried amid thousands of words. How could my brain have picked it out in that fraction of a second? Why? (Well, one can guess why.)

We imagine memory works like a video camera. Not so. The brain does hold such information, but only briefly, then discards it. What it retains is only a bare thematic outline. When you later “remember,” what the brain does is to refer to that outline and to fill in the details by, basically, making them up. Really! And those confabulations change over time. (This is why “eyewitness testimony” in courts is often specious.)

This was brought home to me when I wrote an autobiographical memoir. I thought my memories were fairly accurate. But checking against diaries written when events were fresh showed how differently I remembered them years later. And when, years later still, I re-read that autobiography, I was surprised yet again to find that my memories had further changed.

And yet the brain does have an uncanny ability to file away information. Recently my wife told me someone said she reminded him of Sheila Miles.

“Sara Miles?” I said.

“Maybe. Who’s that?”

“Actress; I think she was in a film – something about an Irish girl and a soldier? I can’t recall the title. Must’ve been 1970, since I do remember the girl I saw it with.” (And I could recall just one scene in that movie. Guess what? Breasts again.)

Next morning, while coming awake (a good time for this), the word “daughter” entered my mind. In another moment, I had it: Ryan’s Daughter.

Now, I’m no film buff, and had you asked me, “Who was in Ryan’s Daughter?” I doubt I could have answered. Yet given the name Miles – even with the wrong first name – my brain made the connection. The information was still there, buried, unthought of, for 44 years.

Then there was the time I greeted my wife with, “Good morning, old man.”

She gave me a quizzical look. “What made you call me that?”

“Why, I have no idea! It just popped out of my mouth.” I’d never said it before.

Well, that night we watched The Third Man, having ordered it from Netflix. I had a vague recollection of having seen it on TV as a kid, nearly half a century earlier. If asked, I couldn’t have told you a thing about that film. Maybe that Orson Welles was in it. Maybe. And seeing the movie again now, nothing seemed familiar.

So I was gobsmacked when the Welles character calls the Joseph Cotten character “old man!”

That tiny detail wasn’t even significant in the film, but somehow, my brain had squirreled it away, and half a century later, unconsciously prompted by our Netflix order, put the words into my mouth, without my even realizing why.

You’re parachuted onto an alien planet. Of course, the language is unlike any you’ve ever heard. In fact, imagine further you don’t know any language – or even what language is. Yet your mission is to decode the language, just by listening, so you can understand and speak it.

One more thing: you’re two years old.

Of course, we all do this. That’s amazing. Seemingly impossible, if you think about it. And what does “think about it” really mean?

I’ve been reading Steven Pinker’s 1997 book, How The Mind Works.* My main conclusion: it can’t.

Though I must admit I don’t understand all of the book. And, to be sure, nobody truly does understand how the mind works. Pinker gives us the best scientific insight.** We do understand a lot, in schematic terms. But I’m the kind of guy who wants to know on a nitty-gritty mechanistic level how the neurons actually carry out the processes and encode the information they’re supposed to. I want to understand how my mind carries a picture of my mother; and nobody can yet really tell me.

In my own last book, I cited the language example above; another was hitting a baseball. As the ball is pitched, the brain has a fraction of a second to gauge its speed and trajectory – a particularly difficult problem because remember that you’re seeing it from the worst possible foreshortened head-on perspective. Then you must calculate the exact mid-air spot where the bat will have to be to intersect with the ball, a window of opportunity lasting milliseconds; then calculate the exact arm movements needed to get the bat to that rendezvous, at the right angle, at exactly the right moment; and finally transmit the requisite instructions to the muscles. All this has to happen in a second or so.

I say it can’t be done. The mathematics are beyond complicated. But, you say, your beer-soaked loser brother-in-law does it regularly? Hmm . . .

Now, leaving aside physical feats like that, you might suppose that pure thought is pretty simple business. You’d be wrong, as Pinker’s book makes clear. Ever the careful analyst, he dissects down to its nitty-gritty what a “thought process” must entail. Suppose you have a bunch of information about a family and want to figure out whether X is Y’s uncle. Simple? Pinker takes us through the logic steps – for pages and pages before you get to the answer. (Reminded me of Principia Mathematica wherein Russell and Whitehead sought to ground mathematics in pure logic and after literally 362 pages finally proved 1+1=2.)

So no thought process is “simple,” not at all, when you really, er, think about it.

And how ‘bout them eyeballs?

Here’s where it gets truly hairy. To begin with, the problems of interpreting what is seen are immense. Remember that baseball coming straight at you. Figuring out what you’re seeing when you see a three dimensional object, with two eyes each seeing a slightly different image, the two having to be collated, with a foreground and a background, together with a whole mess of other objects, some of them partly in front of others, under variable lighting conditions, that may be right side up or upside down, near (and seemingly large) or far (and seemingly small), and moving at great speed besides – whoa!

Nobody has ever been able to program a computer that comes remotely close to sorting this out.

But that’s only the beginning. The really hairy problem is how the results of such visual interpretation are seen by the mind. No, there isn’t a little man in there viewing images projected on a screen. Now, as I sit here writing this, I “see” a rather complicated scene. You could render it into language – there’s a vase of a certain shade of blue, of a certain shape, with a bunch of a certain kind of flowers in a certain configuration, in front of another one . . . to actually get in all the details would take quite a lot of verbiage, that could fill a book; and it all could be encoded into ones and zeroes, like a computer does with pixels. And the brain could process that. But what I’m seeing is not a welter of ones and zeroes. I see an image. How can that be? Without a little man?

Pinker actually suggests that at least part of it involves literally physically mapping a picture across the brain. He cites an experiment with a monkey viewing a bull’s eye target, with a brain scan of neural activity showing a similar bull’s eye pattern. Well, maybe. But I can’t be convinced that such a mechanism accounts for the finely-grained complexity of what I’m seeing right now.

And this all concerns seeing what’s in front of us. But we can see other things. Things we remember (like that picture of my mom). And things we only imagine.

Dreams of flying are common. In mine, I can swoop at high speed over a landscape of great intricacy, changing by the millisecond. How does my brain create that imagery? Sometimes I wonder whether it’s as simple as a program instructing me to imagine I’m seeing a complex landscape. But how would my imagination comply, supplying what is certainly experienced as detailed visual imagery?

It’s a chicken-and-egglike conundrum. I can accept that visual information goes from eye to brain, and the brain can know what’s being seen. But, again, how do we experience it not as information but as a picture? There’s got to be a little man in there! (And of course a little man inside his head . . . )

That’s why I say this too can’t be done.

But, to be serious, the point is what a fantastically advanced, profoundly subtle technology the human mind is – far more than anything Apple has come up with. And I haven’t even mentioned consciousness! Siri is one smart cookie, but doesn’t know she exists, and that’s a giant chasm between us.

Religious believers look at all this and say it could only have been designed by a divine intelligence. I draw the opposite conclusion. I can’t see any single mind, no matter how divine and omnipotent, designing such a system from scratch. It could only have evolved stepwise over eons of time by an iterative natural trial-and-error process. And, of couse, if you do envision a divine intelligence capable of such a feat – who the heck designed that mind? As Pinker says, religion answers baffling mysteries with ones even more baffling.

* A little out of date, admittedly, but while our understanding of the subject has grown since then, it has not radically changed.

** And being Pinker, it’s not all dry and pedantic. One topic deeply explored is how the mind works in sexuality. He quotes an older hooker mentoring a younger one who can’t understand a rich handsome man paying for sex. “Honey,” she’s told, “he’s not paying you for the sex. He’s paying you to go away afterward.”